R: Registry creator

registry {registry} | R Documentation

## Registry creator

### Description

Function to create a registry object.

### Usage

    registry(entry_class = NULL, registry_class = NULL,
             validity_FUN = NULL, stop_if_missing = FALSE)

### Arguments

`entry_class` | character string indicating a class the returned registry object will additionally inherit from (optional). Used for dispatching user-specified print and summary methods.
`registry_class` | character string indicating a class the registry entries will additionally inherit from (optional). Used for dispatching user-specified print and summary methods.
`validity_FUN` | a function accepting a new registry entry as argument for checking its validity and possibly aborting with an error message. The entry will be provided by the calling function as a list with named components (fields).
`stop_if_missing` | logical indicating whether the registry lookup functions should abort or just return `NULL` in case of no match.

### Details

This is a generating function that will return a registry object whose components are accessor functions for the contained data. These are documented separately (`regobj`).

### Author(s)

David Meyer David.Meyer@R-project.org

### See Also

`regobj`

### Examples

    R <- registry()

    R$set_field("X", type = TRUE)
    R$set_field("Y", type = "character")
    R$set_field("index", type = "character", is_key = TRUE,
                index_FUN = match_partial_ignorecase)
    R$set_field("index2", type = "integer", is_key = TRUE)

    R$set_entry(X = TRUE, Y = "bla", index = "test", index2 = 1L)
    R$set_entry(X = FALSE, Y = "foo", index = c("test", "bar"), index2 = 2L)

    R$get_entries("test")
    R[["test", 1]]
    R["test"]
    R[["test"]]

[Package registry version 0.5 Index]